Liquid storage bag

ABSTRACT

A standing-pouch liquid storage bag in which a bottom forming film folded in half is disposed with a crease provided on the upper end of the bottom forming film at a predetermined position of a bag sheet material folded in half with one side, a bottom side and an other side of the liquid storage bag are closed by heat sealing, and heat sealing is performed on a portion of the one side except for a given length from the upper end of the liquid storage bag to construct a bag main part, wherein at least the one side is cut so as to align one end of the bottom forming film with the side portion of the bag main part, so that the lower part of the liquid storage bag is narrower than the upper part of the liquid storage bag.

Field of the Invention

The present invention relates to a liquid storage bag for storing aliquid such as a detergent.

BACKGROUND OF THE INVENTION

Japanese Patent Laid-Open No. 11-70947 discloses a known liquid storagebag of the prior art. The liquid storage bag is, for example, a liquidsealing bag provided with a gore portion on the lower end and having theside edges and the upper edge closed to form a liquid storage spacehaving a bottom, so that the bag can stand by itself while storing aliquid in the liquid storage space. The upper edge has a sealing overlapportion that is shaped like a belt with a fixed width, the liquidstorage space is formed so as to protrude at least to one side of thebelt-like overlap portion, and the overlap portion having the protrudingliquid storage space is cut to form a spout on the end of the bag. Theoverlap portion has a V-cut portion for dividing the protruding portionof the liquid storage space and the other portion.

When the liquid is collected from the storage bag disclosed in JapanesePatent Laid-Open No. 11-70947, the sealing portion having the spout iscut off on the end of the spout and then the liquid in the storage bagis collected from the spout by tilting the storage bag.

When the liquid is collected from the storage bag disclosed in JapanesePatent Laid-Open No. 11-70947, the sealing portion having the spout iscut off on the end of the spout and then the liquid in the storage bagis collected from the spout by tilting the storage bag. Since theperiphery of the storage bag is closed by heat sealing, the sealingportion is cut off on the end of the spout and then the liquid in thestorage bag is collected from the spout by tilting the storage bag. Alarge amount of the liquid in the storage bag is smoothly poured fromthe spout, however, an air flow into the storage bag becomesinsufficient as the amount of liquid in the storage bag decreases, andthe inner surfaces of side sheets forming the storage bag come intocontact with each other near the sealing portion on both sides of thespout, that is, the spout is substantially closed. Thus even when thestorage bag is tilted to collect the liquid in the storage bag from thespout, the liquid is not smoothly poured and it takes a long time tocompletely collect the liquid in the storage bag.

In order to solve this problem, Japanese Utility Model Laid-Open No.3140172 discloses a known storage bag that is a self-standing pouch.

The standing-pouch storage bag disclosed in Japanese Utility ModelLaid-Open No. 3140172 is formed by folding a bag sheet material in half.Relative to one side of the storage bag, that is, the folded side, thebottom side and the other sides of the storage bag are closed by heatsealing. The one side of the storage bag is heat-sealed except for aportion near the upper end of the storage bag to construct the main partof the storage bag. On the upper side of the main part, an inlet openingfor filling the main part with contents is provided at a position notclose to the portion having not been heat-sealed near the upper end ofthe storage bag on the one side of the storage bag, a recessed portionis formed next to the inlet opening on the upper end of the main part ofthe bag while leaving a portion as a content spout opening on theportion having not been heat-sealed near the upper end of the storagebag on the one side of the storage bag, and heat sealing is performedalong the recessed portion. Further, a device for cutting is formed onthe heat-sealed portion of the recessed portion opposed to the portionhaving not been heat-sealed near the upper end of the storage bag on theone side of the storage bag, and the upper side of the main part of thebag is closed by heat sealing in a state in which the main part isfilled with the contents. The storage bag is cut from the device forcutting to the portion having not been heat-sealed near the upper end ofthe storage bag on the one side of the storage bag, so that the contentspout opening can be formed.

According to the configuration of the storage bag disclosed in JapaneseUtility Model Laid-Open No. 3140172, when a liquid is collected from thestorage bag, a portion above the device for cutting is cut from thedevice for cutting to the portion having not been heat-sealed near theupper end of the storage bag on the one side of the storage bag, so thatthe content spout opening is formed. And then, when the storage bag istilted to collect the liquid, the portion having not been heat-sealed isplaced under the content spout opening, so that the liquid flows out ofthe edge of an opening formed on the portion having not beenheat-sealed. At this point, the sheet inner surfaces of the front sideand the back side of the storage bag hardly come into contact with eachother on the portion having not been heat-sealed, so that the contentssmoothly flow out of the storage bag.

In the case of the standing-pouch storage bag disclosed in JapaneseUtility Model Laid-Open No. 3140172, as shown in FIG. 6, a film 2forming the bottom is supplied at a predetermined position on the innersurface of a bag sheet material 1 to be folded into half. In this state,the bag sheet material 1 is folded into half as shown in FIG. 7, andthen heat sealing is performed at predetermined points of the bag sheetmaterial 1 to fabricate the storage bag. In this method, however, whenthe supplied bottom forming film 2 protrudes out of folded portions 3 ofthe bag sheet material 1, the ends of the bottom forming film 2 are bentwith the folded bag sheet material 1, so that the bag sheet material 1and the bottom forming film 2 cannot be normally heat-sealed. In orderto solve this problem, it is preferable to accurately supply the bottomforming film 2 so as to align the ends of the bottom forming film 2 withthe folded portions 3. However, mechanical alignment requires extremelyhigh accuracy that is quite difficult to obtain in reality. FIGS. 6 and7 are explanatory drawings showing that two liquid storage bags aresimultaneously manufactured in parallel.

The present invention has been devised to solve the problem. An objectof the present invention is to provide a liquid storage bag in which oneend of a bottom forming film is not partially bent with a folded bagsheet material, and the one end of the bottom forming film is alignedwith a side of the liquid storage bag.

DISCLOSURE OF THE INVENTION

A liquid storage bag of the present invention is a standing-pouch liquidstorage bag in which a bag sheet material is folded in half with afolded side serving as one side of the liquid storage bag, a bottomforming film folded in half is disposed at a predetermined positionbetween the front sheet and the back sheet of the folded bag sheetmaterial with a crease provided on the upper end of the bottom formingfilm, the bottom side and the other side of the liquid storage bag areclosed by heat sealing, heat sealing is performed on a portion of theone side except for a given length from the upper end of the liquidstorage bag to construct a bag main part, an inlet opening for fillingthe bag main part with a liquid is provided on the upper side of the bagmain part, the upper side of the bag main part is closed by heat sealingin a state in which the bag main part is filled with the liquid, and aliquid spout opening is formed by cutting the upper end of the bag mainpart to a portion having not been heat-sealed on the one side, whereinof the one side and the other side, at least the one side has a portionwhere the bottom forming film disposed between the front sheet and theback sheet of the bag sheet material exists and the one side is cut soas to align one end of the bottom forming film with the side portion ofthe bag main part, so that dimensions between both sides of the liquidstorage bag are smaller on the lower part of the liquid storage bag thanon the upper part of the liquid storage bag.

As has been discussed, in a liquid storage bag of the present invention,at least one side of a folded bag sheet material has a portion where thebottom forming film disposed between the front sheet and the back sheetof the bag sheet material exists and the one side is cut so as to alignone end of the bottom forming film with the side portion of a bag mainpart, so that dimensions between both sides of the liquid storage bagare smaller on the lower part of the liquid storage bag than on theupper part of the liquid storage bag. Thus even when the bottom formingfilm is supplied in the bag sheet material folded in half, it ispossible to achieve a liquid storage bag in which the one end of thebottom forming film and the side portion of the bag main part arepreferably bonded to each other by heat sealing at least on the one sideof the liquid storage bag.

A liquid storage bag of the present invention is a standing-pouch liquidstorage bag for storing a liquid such as a detergent.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a front view showing a state before a liquid storage bag isfilled with contents according to a first embodiment of the presentinvention;

FIG. 2 is a perspective view showing the state before the liquid storagebag is filled with the contents;

FIG. 3 is a front view showing a state after the liquid storage bag isfilled with the contents;

FIG. 4 is an explanatory drawing showing a state of the fabrication ofthe liquid storage bag;

FIG. 5 is a front view showing a state before a liquid storage bag isfilled with contents according to a second embodiment of the presentinvention;

FIG. 6 is an explanatory drawing showing a state in which a bottomforming film is supplied on a bag sheet material, for the explanation ofProblem to be Solved by the Invention; and

FIG. 7 is an explanatory drawing showing a state in which the bag sheetmaterial is folded in half, for the explanation of Problem to be Solvedby the Invention.

DESCRIPTION OF THE EMBODIMENTS

Embodiments of the present invention will be specifically describedbelow in accordance with the accompanying drawings.

Referring to FIGS. 1 to 4, a liquid storage bag according to a firstembodiment will be first described below.

Basically, the liquid storage bag of the first embodiment is formed byfolding a bag sheet material 11 into half. The folded side of the liquidstorage bag is called one side 12, and a bottom side 13 and an otherside 14 are closed by heat sealing. Heat sealing is performed on aportion of the one side 12 except for a given length from the upper endof the liquid storage bag. A bag main part 15 is constructed thus. On anupper side of the bag main part 15, an inlet opening 18 for filling thebag main part 15 with contents is provided at a position not close tothe upper end of a portion 17 having not been heat-sealed on the oneside 12. On the upper end of the bag main part 15, a portion serving asa liquid spout opening 19 is provided that is close to the portion 17having not been heat-sealed and has an upper end closed by heat sealing.Between the portion serving as the liquid spout opening 19 and the inletopening 18, a V-recessed portion 20 is formed along which heat sealingis performed. Further, a notch 22 serving as a device for cutting isformed on a heat sealing portion 21 of the recessed portion 20 opposedto the upper end of the portion 17 having not been heat-sealed on theone side 12 (see FIGS. 1 and 2). In a state in which the bag main part15 is filled with a liquid, the upper side 16 of the bag main part 15 isclosed by heat sealing as shown in FIG. 3. The bag main part 15 is cutfrom the notch 22 to the portion 17 having not been heat-sealed on theone side 12, so that the liquid spout opening 19 can be formed.

In this configuration, the liquid storage bag of the present embodimenthas a bottom forming film 23 disposed in a horizontal position at apredetermined position between the front sheet and the back sheet of thebag sheet material 11 folded in half. The bottom forming film 23 isfolded in half with a crease on the upper end of the bottom forming film23. The front sheet and the back sheet of the bag sheet material 11 andthe bottom forming film 23 are bonded to each other by heat sealing toform a standing pouch. Particularly, in the embodiment illustrated bythe drawings, heat sealing is not performed, on the one side 12 of thebag main part 15, on a portion from the upper end of the liquid storagebag substantially to at least the height of the lower end of theV-recessed portion 20, and the other portion of the one side 12 isheat-sealed. In the drawings, heat-sealed portions are diagonallyshaded.

In the fabrication of the standing-pouch liquid storage bag, it isdifficult to accurately supply the bottom forming film 23 between thefront sheet and the back sheet of the bag sheet material 11 so as toalign one end of the bottom forming film 23 with the folded one side 12,as has been described in Problem to be Solved by the Invention. Thus theone end of the bottom forming film 23 is slightly separated from thefolded one side 12 to prevent the end of the bottom forming film 23 frombeing bent with the folded one side 12. On the other side 14, the bottomforming film 23 is disposed so as to have the other end aligned with theother side 14 (see FIG. 4). In this state, necessary heat sealing isperformed on the overall storage bag as well as on the bottom of thestorage bag as previously mentioned in the foregoing explanation. Thebottom forming film 23 at the lower end of the storage bag in this statehas the one end not aligned with the one side 12 of the liquid storagebag, and then the lower end side of the one side 12 is cut so as toalign the one end of the bottom forming film 23 with the one side 12 ofthe bag main part 15. In the embodiment illustrated in the drawings, thelower end side of the other side 14 is cut like the one side 12. Inother words, as shown in the drawings, dimensions between both sides ofthe liquid storage bag are smaller on the lower part of the liquidstorage bag than on the upper part of the liquid storage bag. Further,on portions to be cut on the one side 12 and the other side 14, heatsealing widths are set in consideration of the cutting margins. That isto say, heat sealing is performed beforehand on the portions to be cuton the one side 12 and the other side 14.

In the first embodiment, both sides of the lower end of the liquidstorage bag are cut. Since the other end of the bottom forming film 23is aligned with the other side 14, it is not always necessary to cut theother side 14, as illustrated in a second embodiment of FIG. 5.

1. A standing-pouch liquid storage bag in which a bag sheet material isfolded in half with a folded side serving as one side of the liquidstorage bag, a bottom forming film folded in half is disposed at apredetermined position between a front sheet and a back sheet of thefolded bag sheet material with a crease provided on an upper end of thebottom forming film, a bottom side and an other side of the liquidstorage bag are closed by heat sealing, heat sealing is performed on aportion of the one side except for a given length from an upper end ofthe liquid storage bag to construct a bag main part, an inlet openingfor filling the bag main part with a liquid is provided on an upper sideof the bag main part, the upper side of the bag main part is closed byheat sealing in a state in which the bag main part is filled with theliquid, and a liquid spout opening is formed by cutting an upper end ofthe bag main part to a portion having not been heat-sealed on the oneside, wherein of the one side and the other side, at least the one sidehas a portion where the bottom forming film disposed between the frontsheet and the back sheet of the bag sheet material exists and the oneside is cut so as to align one end of the bottom forming film with theside portion of the bag main part, so that dimensions between both sidesof the liquid storage bag are smaller on a lower part of the liquidstorage bag than on an upper part of the liquid storage bag.